Given, for example, legislation arising from the global warming problem, there are demands for strengthened control of the quantity of energy used in factories and manufacturing lines. Because heat-producing equipment and air-conditioning equipment are facilities equipment that can consume a particularly large quantity of electricity, often the upper limit for the quantity of energy consumed is controlled so as to be kept lower than the maximum value in conventional equipment. For example, in facilities equipment that runs on electric power, the operations are performed in particular so that the quantity of electricity used will be within specific limitations prescribed by an electric power demand controlling system. In particular, there have been proposals for methods, such as described below, for limiting the total quantity of electric power that is supplied simultaneously at the time of startup in heat-producing equipment that is provided with a plurality of electric heaters (when heating up simultaneously the temperature in multiple areas wherein electric heaters are installed).
In the reflow equipment disclosed in Japanese Patent 2885047 (“JP '047”), in order to reduce the quantity of electric current consumed at the time of startup, the startup time bands are offsetted from each other so that one heater is started up after the thermal saturation of the vicinity of the previous heater. In the semiconductor wafer processing equipment disclosed in Japanese Unexamined Patent Application Publication H11-126743 (“JP '743”), electric power is provided while providing timing differences for the individual heaters, so as to not consume large quantities of electric power all at once at the time of equipment startup.
In the substrate processing device disclosed in Japanese Unexamined Patent Application Publication H11-204412 (“JP '412”), in order to reduce the maximum electric power that is provided at a given time from an electric power providing portion, a specific startup sequence is followed and each of the heat treating portions are started up sequentially, one at a time. In the heating device disclosed in JP '743, in order to prevent electric power damage due to an excessive consumption current at the time of starting up the equipment, first the electric power that is necessary for the heater that is positioned below a conveyor is provided, and the electric power that is applied to heaters that are positioned above the conveyor is controlled in order to control the total quantity of electrical power consumed so as to be below a specific value, and as the temperature within the furnace increases, the temperature is used as a switching parameter, to perform control so as to reduce the quantity of electrical power supplied to the heaters that are positioned below the conveyor.
In the technologies disclosed in JP '047, JP '743, JP '412 and Japanese Patent 4426155 (“JP '155”), in all cases the use of the method of supplying the electric power through providing timing differences to a plurality of heaters causes the heating efficiency to the poor, or in other words, there is a problem in that the following performance for a controlled quantity PV (temperature) in relation to the setting value SP in step response is poor.
Because there will always be some degree of variability in the time required in order to start up the equipment and in the electric power required at startup when electric power is supplied through providing time differences to a plurality of heaters in manufacturing equipment, it is necessary to perform the switching evaluations with surplus availability when starting up by providing time differences. Consequently, when starting up (heating up) heating equipment that is provided with, for example, four heating/controlling systems, when the heating/controlling systems are started up individually and sequentially, ultimately an amount of time that is no less than the time wherein the time for starting up one system has been multiplied by four will be used.
Moreover, in order to facilitate ease in the startup switching evaluation, innovations are considered wherein the electric power is supplied in a sequence that is determined for heaters at specific positions, as in the technology disclosed in JP '155. However, the technology disclosed in JP '155 is a method that is used only when starting up in exactly identical patterns, and cannot the apply when there are changes in the heating requirements depending on manufacturing conditions. The more the method diverges from the most efficient method, that is, the normal simultaneous heating wherein electric power is supplied simultaneously to the plurality of heaters, the greater the problems with either a reduction in heating efficiency or in limitations to applicability.
The present invention was created in order to solve the problems set forth above, and the object is to provide a total energy limiting and controlling device and total electric power limiting and controlling device and method able to perform control so that the quantity of energy used (for example, the quantity of electrical power used) in step-response control does not exceed a prescribed value that has been specified, and so that, insofar as is possible, setting value following performance is not lost.